The Dynamic Dependent And-parallel Scheme (DDAS) is a parallel executi
on scheme for Prolog that is designed to exploit independent and depen
dent and-parallelism in full Prolog programs. In this paper, an overvi
ew of some techniques for implementing DDAS is presented. The main pur
pose of these techniques is to provide reasonably efficient methods fo
r implementing the idea of the dependent status and the dynamic detect
ion of the leftmost instance of a variable, along with the techniques
needed for suspending and waking up of goals. DASWAM, an implementatio
n of DDAS using the techniques presented in this paper, is based on mo
difying the Warren Abstract Machine (WAM) for parallel execution, and
is designed to execute programs efficiently. A prototype DASWAM has be
en implemented, and results on running significant application program
s presented in this paper suggest that it is possible to implement DAS
WAM efficiently, and that significant parallelism can be extracted.